§ Задание 21
\[\boxed{\mathbf{21.}}\]
\[34 + 26 = 60\]
\[29 + 21 = 50\]
\[42 + 28 = 70\]
\[38 + 12 = 50\]
\[53 + 27 = 80\]
\[45 + 35 = 80\]
\[61 + 39 = 100\]
\[77 + 23 = 100\]
\[\boxed{\mathbf{21.}}\]
\[34 + 26 = 60\]
\[29 + 21 = 50\]
\[42 + 28 = 70\]
\[38 + 12 = 50\]
\[53 + 27 = 80\]
\[45 + 35 = 80\]
\[61 + 39 = 100\]
\[77 + 23 = 100\]